New belt is WAY too short

Just replaced the motor and control on this machine, and thought it might be a good idea to replace the 16 year old belt at the same time. Ordered the correct belt, but it is at least 2" shorter than the old one, and even with the adjuster at the lowest number, there is no way it will stretch over the large pulley. Put the old one back on to get the machine running, but before I give up and send this new belt back, thought I'd ask: Is there something I'm missing here ????

Thanks !!!